Search results for "Reactive"
showing 10 items of 1469 documents
Electrochemical characterization of mangrove sediments: A proposal of new proxies for organic matter oxidation
2019
Abstract The voltammetric response of microparticulate deposits resulting from solvent evaporation of ethanolic extracts of mangrove sediments in contact with aqueous acetate buffer is hereby described. Dated sediment cores sampled from the Peruvian mangrove system (“Manglares de Tumbes” National Sanctuary) presented voltammetric responses dominated by oxidative signals of organic components that exhibit significant variations depending on the depth. Voltammetric data allowed for the definition of electrochemical indexes representative of the electrochemically oxidable organic matter fraction. These electrochemical indexes were fEAOM (for the total amount of organic matter being electrochem…
Chemiluminescence response of ß-glucan stimulated leukocytes isolated from different tissues and peritoneal cavity of Dicentrarchus labrax
2003
Abstract The respiratory burst of leukocytes isolated from sea bass ( Dicentrarchus labrax ) pronephros, peritoneal cavity (P.C.), spleen and blood, was measured by a chemiluminescence (CL) assay after stimulation with β-glucan. The CL response by P.C. and pronephros leukocytes was significantly higher than that expressed by a similar number of cells separated from spleen and blood. This probably reflects the observation that the proportion of macrophages and neutrophils was highest in the populations of leukocytes from peritoneal cavity and pronephros. Comparative observations showed a higher degree of yeast phagocytosis by leukocytes taken from peritoneal cavity than the pronephros. Moreo…
Confinement stress in sea bass (Dicentrarchus labrax) depresses peritoneal leukocyte cytotoxicity
2002
Fish respond to stressful conditions via neuroendocrine responses (primary response) which result in increased levels of plasma cortisol which is considered immunosuppressive. Sea bass were confined at low (10 kg/m3) and high (60 kg/m3) density for 3-48 h. Plasma cortisol and glucose were evaluated and two principal cellular immune responses were assayed. A significant increase in plasma cortisol and glucose levels, as well as osmolarity, was found following stress. In addition, phagocytic activity, as shown by reactive oxygen species (ROS) production by challenged head kidney phagocytes and cytotoxic activity of eosinophilic granule cells from peritoneal cavity against K562 tumour cell lin…
Short-Time Ocular Ischemia Induces Vascular Endothelial Dysfunction and Ganglion Cell Loss in the Pig Retina
2019
Visual impairment and blindness are often caused by retinal ischemia-reperfusion (I/R) injury. We aimed to characterize a new model of I/R in pigs, in which the intraocular pathways were not manipulated by invasive methods on the ocular system. After 12 min of ischemia followed by 20 h of reperfusion, reactivity of retinal arterioles was measured in vitro by video microscopy. Dihydroethidium (DHE) staining, qPCR, immunohistochemistry, quantification of neurons in the retinal ganglion cell layer, and histological examination was performed. Retinal arterioles of I/R-treated pigs displayed marked attenuation in response to the endothelium-dependent vasodilator, bradykinin, compared to sham-tre…
Brief Report: Intestinal Dysbiosis in Ankylosing Spondylitis
2015
Objective Ankylosing spondylitis (AS) is a common, highly heritable immune-mediated arthropathy that occurs in genetically susceptible individuals exposed to an unknown but likely ubiquitous environmental trigger. There is a close relationship between the gut and spondyloarthritis, as exemplified in patients with reactive arthritis, in whom a typically self-limiting arthropathy follows either a gastrointestinal or urogenital infection. Microbial involvement in AS has been suggested; however, no definitive link has been established. The aim of this study was to determine whether the gut in patients with AS carries a distinct microbial signature compared with that in the gut of healthy contro…
Oxidative stress in cardiovascular disease: successful translation from bench to bedside?
2007
Over the last decades, sound evidence has been generated that oxidative stress is one of the most potent inductors of endothelial dysfunction and is involved at all stages of atherosclerotic plaque evolution.1,2 Experimental and animal models provide a clear association between the amount of oxidative challenge and reversible vascular dysfunction that can be observed before permanent alterations of the vessel wall occur. Article p 1367 Important for cardiovascular biology is the consumption of nitric oxide (NO) by reactive oxygen species. Endothelium relaxant factor is a central molecule in vascular homeostasis as a modulator of endothelial tone and reactivity.3 It is produced by NO synthas…
Effect of a 1-year elastic band resistance exercise program on cardiovascular risk profile in postmenopausal women
2018
Objective: The aim of this study was to investigate the effects of a 1-year progressive resistance training program using elastic bands on cardiovascular profile parameters in sedentary postmenopausal (>12 months’ amenorrhea) women. Methods: This longitudinal prospective experimental study included 38 menopausal women who were randomly divided into two groups: an intervention group (IG, n = 18), who completed a progressive resistance training program with elastic bands over the course of 12 months (six exercises for whole body training, three sets × 10 repetitions), and a control group (CG, n = 20) that did not perform any training. Blood analysis and body composition were determined at bas…
Coptis chinensis Franch. exhibits neuroprotective properties against oxidative stress in human neuroblastoma cells.
2014
Abstract Ethnopharmacological relevance The dried rhizome of Coptis chinensis Franch. (family Ranunculaceae ) is traditionally used in Chinese medicine for the treatment of inflammatory diseases and diabetes. Recent studies showed a variety of activities of Coptis chinensis Franch. alkaloids, including neuroprotective, neuroregenerative, anti-diabetic, anti-oxidative and anti-inflammatory effects. However, there is no report on the neuroprotective effect of Coptis chinensis Franch. watery extract against tert -butylhydroperoxide ( t -BOOH) induced oxidative damage. The aim of the study is to investigate neuroprotective properties of Coptis chinensis Franch. rhizome watery extract (CRE) and …
Red wine extract prevents neuronal apoptosis in vitro and reduces mortality of transgenic mice.
2007
In this work, we have investigated the effects of nutritional antioxidants as antidegenerative agents on glutamate-induced apoptosis in primary cultures of cerebellar granule neurons (CGNs). Glutamate-induced apoptosis is also associated with intracellular [Ca(2+)]i overload, generation of reactive oxygen species (ROS), depression of cell energy metabolism, cytochrome c release, and increase in caspase-3 activity. Pretreatment (3 h) with red wine extract (5 microg/mL) and ascorbic acid (30 microM) blocks glutamate-induced apoptosis in CGNs. In vivo experiments carried out on transgenic mice expressing the human mutated Cu, Zn superoxide dismutase (SOD1) G93A (mSOD1(G93A)) show that mice fed…
Engineered Trx2p industrial yeast strain protects glycolysis and fermentation proteins from oxidative carbonylation during biomass propagation
2012
Abstract Background In the yeast biomass production process, protein carbonylation has severe adverse effects since it diminishes biomass yield and profitability of industrial production plants. However, this significant detriment of yeast performance can be alleviated by increasing thioredoxins levels. Thioredoxins are important antioxidant defenses implicated in many functions in cells, and their primordial functions include scavenging of reactive oxygen species that produce dramatic and irreversible alterations such as protein carbonylation. Results In this work we have found several proteins specifically protected by yeast Thioredoxin 2 (Trx2p). Bidimensional electrophoresis and carbony…